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本帖最后由 passagere 于 2017-6-29 05:25 编辑
! _& |+ `5 j8 f2 ?, ^5 xsheleason 发表于 2017-6-27 18:12 # I( p8 b/ F: ?7 H; u8 ^
借楼问一下。有款灯具 输入线是3线 里面连接的内置电源。灯具外壳是金属 但是外壳没有接地。
/ \) S! @. U" ?。灯具的输入 ...
5 w* r9 G! R; u* Q& [. o2 y按60598,地线没有连接到可接触的金属部件上时,可以作为II类灯具(同时满足II类结构要求)。II类灯具不需要做接地连续性测试。GND到地线上不传导绝缘失效时的危险电流,所以不需要做。4 i2 @: p: q- E3 B6 U
* B$ }7 k6 B8 `5 ?; i; H/ y5 {% mGND上到地线,是为了功能或者电磁兼容的作用,不是为了传播电流的。如果I类灯具,且PCB上的铜箔作为传输路径时(I类灯具上也有功能接地部分,不是接到PCB上就一定对trace有大电流传播要求),那是需要额外验证大电流通过能力的。路径为:地线——PCB trace——可能带电的金属部件时,trace才可能传播大电流。) w* @9 V& _0 n1 Z
% c( \9 h% ~2 U+ S8 F% s$ g在60598里找到条款,按II类灯具判就可以了。3 D3 w; ]0 H! A1 b( ^6 |+ m; \) i9 ?
1.2.23% ^9 D1 X9 W! X) P! y3 [. p9 \' T7 h
class II luminaire \8 b; s0 @! ?5 h; Z
luminaire in which protection against electric shock does not rely on basic insulation only, but in
; G; O( r+ n4 @9 `6 j1 nwhich additional safety precautions such as double insulation or reinforced insulation are3 o" I9 G2 \' _, Y4 d5 z. m
provided, there being no provision for protective earthing or reliance upon installation
# H, b& N' F/ xconditions
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' U6 H& h+ w8 g9 BNote 3 to entry: If earthing is provided to assist starting, or for EMC reasons, but is not connected to an
' Y* q1 A! e5 C! h9 p) W. taccessible metal part, the luminaire may still be deemed to be of class II. Accessible metal parts in compliance with3 D r" j* G0 h$ x0 Q8 B f7 z. C
the appropriate IEC lamp specification and other metal parts not normally earthed and not normally accessible9 f: t2 n- V8 w" k) I6 t
during normal use are not regarded to be conductive parts which may cause an electric shock unless the tests of p) J2 q" ]' m9 J
Annex A show them to be live parts.
3 {3 g" [9 ~$ m& Q7 w/ t* m1 s7 p$ [/ b6 _0 @0 _* g$ u9 ]/ b% \" U! {- j
8 W) Q3 x* a; H- `! [从上面条款可以看出,功能接地的灯具,满足要求时可以判为I类灯具。具体判定位I还是II,看结构特点和那个更容易实现、简单。7 z& J' I [) P9 j4 g7 ]- l
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